Improvement in piston-packings



Pn'rnlv'rV OFFICE.

S. LLOYD WEIGAND, OF PHILADELPHIA, PENNSYLVANIA.

`IMPROVEMENT IN PISTON-PACKINGS.

Specification forming part of Letters Patent No. 119,100, dated September 19, 1871.

To all whom t may concern.' l

Be it known that I, S. LLOYD WIEGAND, of the city and countyM of `Philadelphia. andState of Pennsylvania,"have" invented a new and useful Improve-nient". in Piston-Packingfor Pumps and Steam-Gyfliriders 5 and Ido hereby declare the following to bena full, clean'andexact description thereof, reference being had tothe drawing anneXed.,-` 1 l Figure l shows a longitudinal section of a cylinder and-,piston -containing this improvement. Fig. 2 shows a transverse section of the cylinder on the plane indicated by the vertical dotted line a bin Fig.1, and with the-follower end removed. Fig. 3 shows a longitudinal section of the tubular irture"V that formsthe prominent characteristic of this'invention; and Figxl, a modification thereof. u .t

The natureofmyinvention consists in corn-` bining two tapering-tubes` leading into the interior cavityof a piston from opposite sides thereof, in such a manner that the smaller end of one tube is made annular and encircles the smaller end of the other tube, and whenever a jet of steam or other iiuid flows through either tube into the cavity of the piston by reason of fluid pressure being applied to either side of the piston, a current of` fluid is induced through the other tube fromthe opposite side of the piston. Fluid pressure is.` thus readily and effectively maintained in the cavityof the piston, and being transmitted through suitable apertures to the inner surfaces of the packing-rings, holds them iu close contact with the inner surface of the cylinder with suiiicient force to render the piston steam-tight, but not enough to occasion injurious friction. p

I will now proceed to particularly describe the manner of making and using my invention, re-

ferring in so doing, by letters of reference, to the "drawing hereto annexed.

The same letters of reference apply to the same parts in the several figures.

A represents a `cylinder provided with a pistonrod, B, bearing upon the end a piston, C, formed of a body or spider, D, secured rmly on the rod B, anda follower, E, secured by several bolts F to the body or spider D. Between the body D of the piston and the follower E, is placed a cy- `lindrical shell, H, turned with shoulders so as to form grooved` recesses, in which are placed packing-rings J and J f. The shell H may be divided and grooved in the center so as to form a recess into which a central supporting-ring, K, may be fitted, which 'may be adj usted concentrically with lthe piston-rod 4B and internal surface or bore of the cylinder A, by means of the set-screws L, provided with lock-nuts M. A number of apertures, N, are drilled, communicating from the cavity in the shell H to the bottoms of the grooves under the packing-rings J and J f. These permit any `fluid pressure in the cavity in the shell H to be transmitted to the interior surface ofthe rings So far as I have described this invention, it coincides with some others that have been previously made and used; but the peculiar characteristic and important feature of my invention consists of a tube, O, leading from one side of the piston and terminating in a tapering nozzle vwhere the conical nozzles terminate in the cavity of the piston. A jet of steam or other fluid flowing into either of thetubes induces a current inward into the cavityof the piston in the same manner that the iiowof steam through an injector draws water into the annular space surrounding the steam-jet. In large pistons several pairs of tubes may be advantageously used in preference to one larger pair. It will be plainly apparent that so long as there is iiuid pressure upon either side of the piston, there will be like pressure or greater in the cavity of the piston and against the inner surfaces of the rings J and J', so that the vrings will be held in close contact with the inner surface or bore of the cylinder with a force always in due proportion to the pressure in the cylinder.

Various modifications can be made of this invention by changing the form of the tube; as, for

to close both the central and annular jets. These are not desirable, but will Work, and do not change the essential feature of the invention.

I am aware that devices have been proposed in which one jet-tube leading from one side of apiston induces a current in a jet-tube leading from the opposite side thereof. This I distinctlyv disclaim; but

What I do claim as my invention, and desire to secure as such b v Letters Patent, is-

An annular jet-tube leading` from one side of the piston, surrounding a jet-tube leading from the opposite side of the piston, inducing currents through each other, and thereby pplying internal pressure to the packing-rings, substantially as described and shown.

In testimony whereof I have signed this specication in the presence of two subscribing Witnesses.

S. LLOYD WIEGAND.

Witnesses:

A. ELLWooD JONES, JOHN B. DEvINE. 

